An enumeration which identifies the attribute being monitored. See also the definition of the corresponding trap. The pctCpuUtilization is monitored for each CPU in the server. The attributes whose name starts with 'physIf', are monitored for each physical network interface on the server. The attributes whose name starts with 'queue', are monitored for each queue on the server. The attributes whose name starts with 'volume', are monitored for each volume on the server. The attributes whose name starts with 'disk' are monitored for each disk on the server. All other attributes have a single instance.